<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <style>
        div{
            border: solid;
        }
        .main{
            /* width: 600px;
            height: 600px; */
            position: fixed;
            top: 0;
            bottom: 0;
            left: 0;
            right: 0;
        }
        .left{
            width: 100px;
            position: absolute;
            left: 0;
            top: 0;
            bottom: 0;
            background-color: antiquewhite;
        }
        .right{
            width: 100px;
            position: absolute;
            right: 0;
            top: 0;
            bottom: 0;
            background-color: antiquewhite;
        }
        .center{
            position: absolute;
            left: 100px;
            right: 100px;
            top: 0;
            bottom: 0;
            background-color: aqua;
        }
    </style>
</head>
<body>
    <div class="main">
        <div class="left">left</div>
        <div class="center">center</div>
        <div class="right">right</div>
    </div>
</body>
</html>